Referring to FIGS. 1 and 2, the anchoring structure for a conventional drum 1 usually includes a rotary dock 2 located respectively on two sides to couple with a telescopic tube 3 for standing on the floor. The telescopic tube 3 has an inner tube 4 and an outer tube 5. A bolt 6 runs through the outer tube 5 to press the inner tube 4 to set the telescopic tube at a desired length. Users may unfasten and fasten the bolt 6 to adjust the length of the telescopic tube 3.
The conventional technique for setting the telescopic tube 3 mentioned above relies on one bolt 6 to press the inner tube 4. The compression area is small and is prone to loose. When the drum 1 is struck for a long period of time and shock occurs constantly, the inner tube 4 is easily deformed and the telescopic tube 3 is prone to shaking. The sound generated by the drum 1 is affected.
FIG. 3 illustrates another conventional anchoring structure. It includes a telescopic tube 3 which consists of an inner tube 4 and an outer tube 5, and a fixing hub 7 and a movable arm 8 coupled with a movable joint 7A so that they may be opened or closed like clam shells. The fixing hub 7 is coupled on the outer tube 5 and fastened by a fastening element 9. The movable arm 8 and the inner tube 4 form a large contact area to make fastening more steady. However, in such a structure the inner tube 4 does not have any support while the fastening element 9 is unfastened, and the inner tube 4 often tilts abruptly. As the drum 1 (referring to FIG. 1) supported by the inner tube is quite heavy, the inner tube 4 could be bent and result in adjustment difficulty later. Moreover, the anchoring angle could be inaccurate and the sound generated by the drum 1 could be affected.